Differential in Ground Potential and Distance
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1. Lightning strike touches the ground.
2. Rings of high energy radiate out from lightning strike and cross ground rod on building #2., causing the power grid to go high in building #2. Building #1 is still at normal.
3. Data line #3 between building #1 and #2 cause equipment in building #2 to be at great potential difference to building #1. Bus lines on computer are at 5-volts or 12-volts and ground has gone way up in voltage. Input and output ports see this tremendous difference and pop the Integrated Circuits. This did not go through the data line surge suppressers where they could have suppressed the over - voltage. It was a difference of potential coming in on ground and coming on behind the surge suppressers bypassing them.
Bond the grounds on buildings #1 and #2 together with heavy cable so building voltage potential will rise and fall as if both buildings were one.
Install fiber optic communication cables between buildings or isolation transformer (s) for remote equipment (terminal in example). Fiber optic cable will not carry electrical charge. Isolation transformers provide electrical isolation for the remote terminal (s) or equipment. The terminal in the example will think it is grounded in building #1.
The less resistance in the building ground lines, the less voltage induced when lightning energy rings cross it. Good grounds are of prime importance.